In typical domestic clothes dryers, venting of exhaust air from the dryer is accomplished by a motor that drives both a blower fan and a transmission system that rotates the dryer drum. The dryer motor is typically a four pole induction motor which rotates at a speed of 1,800 revolutions per minute (rpm). The blower fan rotates to draw air from the dryer drum and forces the air out of the clothes dryer through an external vent mounted to an outlet port of the clothes dryer. The dryer motor is able to exhaust air from the dryer along the external vent for distances up to about 90 feet when there are no elbows or bends in the external vent. It should be understood that this exhaust venting may have bends and corners as it extends between the dryer outlet and a laundry room outlet vent. Also, further restrictions in this external vent may occur as a result of lint and dust build up inside the external vent.
In some new home applications, there is a requirement for the use of external vents that are longer in length than 90 feet and are upwards of 130 and 150 feet. These applications in the industry are referred to as long venting applications. Due to the longer length of these vents and the  increased air flow restriction associated with pushing the air flow through a longer vent channel, the four pole motor connected directly to the blower fan does not generate sufficient air flow pressures to exhaust the dryer air along the longer vent channel.
There currently exists on the market a long vent clothes dryer adapted to operate with external vents extending to as much as 120 feet in length. This long vent clothes dryer incorporates a pulley transmission system that connects the blower fan with the four pole motor whereby the pulley transmission system effectively increases the speed of rotation of the blower fan and air pressure generated by the blower fan. While this system is believed to operate for external vent lengths up to 120 feet, in other applications lengths of 150 feet of external venting may be required.
Further, when a domestic major appliance manufacturer does not have a long venting clothes dryer solution, that manufacturer typically loses supplying a complete line of major appliances to new domestic housing projects requiring a long vent dryer application. In particular, the builder has a tendency to select the same line of appliances for all 5 or 6 major appliances provided in a home. When a long venting requirement must be met, the builder will usually order a complete line of major appliances from those manufactures with proven long venting clothes dryers.
Accordingly, there is a need to provide a clothes dryer which is suitable for use in a long venting application.